Example: Load balancing for web servers

To configure and monitor load balancing for multiple web servers, you can set up a Server Pool and install Monitoring Agents on the individual servers.

Company A has three web servers to handle the large volume of traffic its website receives. The administrators have already created Host elements to represent their web servers and created NAT rules to assign an external address to each web server.

Now the administrators want to distribute the load of the traffic between the servers. The administrators also want to monitor the status and the load of the servers, and receive an alert whenever one of the web servers in the Server Pool fails. The administrators decide to set up a Server Pool and install Monitoring Agents on the web servers. The administrators:
  1. Delete the existing NAT rules that translate the IP address of each server so that the Server Pool can do automatic NAT without conflicts.
  2. Create a Server Pool element and add the Host elements to it. Because they are not balancing incoming connections to the Server Pool between multiple Internet connections, the administrators select the Not Specified NetLink.
  3. Install a Server Pool Monitoring Agent on each server in the Server Pool and configure the Monitoring Agents to measure the load average on the server. They also set up a test that checks each server’s connectivity every 60 seconds and sends an alert if the test fails.
  4. Enable the Server Pool Monitoring Agents in the Server Pool element.
  5. Add the following IPv4 Access rules in the Firewall policy to allow HTTP connections from addresses that are not internal (Not Internal expression) to the Server Pool.
    Source Destination Service Action
    Not Internal expression Server Pool element HTTP Allow